1. Field of the Invention
This invention relates generally to control devices for directing the motion of a moving equipment, and more particularly to a line feeler assembly for adjusting the height of concrete poured from a moving extruder.
2. Description of Related Art
The following art defines the present state of this field:
Catenacci, U.S. Pat. No. 3,363,524 describes a curb extruding machine.
Lowen et al., U.S. Pat. No. 3,636,833 describes how concrete may be laid to a surface by a datum wire extending e.g. over rough ground by a machine including a mobile carriage with a concrete hopper feeding concrete between slip forms in a controlled fashion using a gate vertically movable in dependence on the movement of sensing devices touching the wire.
Miller et al., U.S. Pat. No. 3,710,695 describes the main frame of a construction machine that is supported upon two pairs of crawler tractors through a five point suspension using four hydraulic rams, two of which cooperate with one pair of tractors and two of which cooperate with the other pair of tractors through a walking beam.
Miller et al., U.S. Pat. No. 3,749,505 describes a machine for handling, conveying, compacting and distributing formable material such as concrete upon or along a work location in the desired grade, slope and directional configuration defined by an external reference extending along the path of travel.
Godbersen, U.S. Pat. No. 3,779,661 describes machine and method that provides for the simultaneous and continuos preparing of a graded surface and the slip forming of a curb and gutter or a sidewalk on the prepared surface.
Smith, U.S. Pat. No. 3,779,662 describes an improved curb slip form apparatus for forming a predetermined, formed configuration of a concrete material of the like on a surface generally along a predetermined survey line, having a form member which is pivotally connected to a support frame, the formed configuration being extruded from the form member, in an operating position of the form member, in an operating position of the form member and in a driven position of the support frame.
Miller et al., U.S. Pat. No. 3,820,913 describes a self-propelled curb and gutter forming machine mounted on continuous traction devices and drawing a mold for the curb and gutter between the traction tread devices.
Rochfort, U.S. Pat. No. 3,864,858 describes a concrete laying machine that includes a frame having a rear portion adjustable or variable in width and carried by a pair of rear tandem wheel supporting assemblies.
Rochfort, U.S. Pat. No. 3,890,055 describes a machine for laying a continuos run of concrete of constant section such as roadway curbing. The machine includes a body portion having a chamber adapted to receive concrete and discharge it rearwardly through an outlet to a mould adapted to shape the discharged concrete to a desired cross-section.
Miller, U.S. Pat. No. 4,197,032 describes an apparatus for concurrently preparing a ground surface and forming a continuos strip of paving material thereon, and which is characterized by the ability to simultaneously grade the ground surface substantially coextensively with the successive slip forming of the pavement material.
Wise, U.S. Pat. No. 4,319,859 describes a self-propelled apparatus for extruding and forming a substantially U-shaped concrete lining within a previously dug ditch and including means for accurately controlling the slope or grade of the interior bottom surface of the lining.
McKinnon, U.S. Pat. No. 5,354,189 describes a manually operable and steerable curb extrusion device for extruding curb, barrier, wall, gutter or the like from concrete, cement or some other moldable building material. The curb extrusion device has a segmented vibrating hopper into which building materials are placed to fall onto two tapered counter rotating vibrating augers which compact and force the building material through and extrusion mold where it is shaped before extrusion.
The prior art teaches the use of a wire for directing the steering and grade control servomechanisms of a moving concrete extruder. The prior art teaches a grade control feeler for cooperation with the wire in determining changes in extruding operation. However, the prior art does not teach a solution to the problem of overcoming obstacles in the path of the wire, nor of overcoming the expense of special overhang-type stakes and the labor required for their use. The present invention overcomes these problems and provides further related advantages as described in the following summary.